<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>多个和覆盖</title>
    <style>
        .c1 {
            color: red!important;
            border: 1px solid black;
        }

        .c2 {
            font-size: 28px;
            color: gold;
        }

        /*多个样式是优先使用下面的*/
    </style>
</head>
<body>

<div class="c1 c2">QWERTY</div>
</body>
</html>